New AR15 feeding issues

[pm123]

I got my AR on 12/31/12. Today is the second day I've ever shot it. The first time shooting I never had a problem. Since then I have replaced the adjustable stock with a magpul prs fixed tube and buffer. The first shot is failing to load when I try to chamber it. The action doesn't close all the way and have to pull the charging handle all the way back or use the forward assist button. Did the gun store sell me too weak of a spring for the fixed buffer? Should I try to put my collapsible spring back in and see if it makes a difference? Or is the gun still too new and needs a break in period? I have 0 experience with AR's other then these 2 times out so I'm not sure what to try.

[TheDigitalPicasso]

I had the same exact issue with my Del-Ton when I purchased it. I then purchased a different spring that was 1 1/2 longer than the one Del-Ton gave me and the problem went away. Also try using FrugLube on the bolt and BCG and that will butter everything up.

Also use a Mil-Spec Buffer tube its a bit shorter and it works better then a commercial, that is if you have a commercial tube.

[clutchy]

the PRS is a rifle length system.

do you have a rifle buffer and spring?

they are different than a carbine or mid-length system.

[pm123]

Yes it's a rifle length tube and spring. I bought it from Sacramento Black Rifle. I told them exactly what I needed it for and what stock it was for. My best guess is it's the spring like TheDigitalPicasso said. So i'll start there and get some of that lube for it. Thanks for the feedback.

[Ruiner]

Yes it's a rifle length tube and spring. I bought it from Sacramento Black Rifle. I told them exactly what I needed it for and what stock it was for. My best guess is it's the spring like TheDigitalPicasso said. So i'll start there and get some of that lube for it. Thanks for the feedback.

Rifle length extension and spring.. do you have a rifle buffer as well?

[pm123]

the PRS is a rifle length system.

do you have a rifle buffer and spring?

they are different than a carbine or mid-length system.

http://i845.photobucket.com/albums/ab13/pmessier/arspring_zps657953d8.jpg

Yes the buffer is 6 inch and the spring about 12.5. The lower one is the old adjustable commercial tube length.

[clutchy]

http://i845.photobucket.com/albums/a...ps657953d8.jpg

Yes the buffer is 6 inch and the spring about 12.5. The lower one is the old adjustable commercial tube length.

huh... that's weird.

I was going to keep probing like "lubed up" etc... but it sounds like you know what you're doing so good luck tracking it down.

Do your feed ramps match up? You're not mixing an A4 upper with an A3 barrel extension?

[markw]

Make sure the BCG is lubed. I'm confused, the BCG doesn't go all the way back? Are you pulling the charging handle back and then riding it forward? Pull the charging handle back and use the bolt release to hold the bolt back, then put your magazine in and press the bolt release and let it "slam" forward. It will strip a round. The buffer tube length and buffer have more to do with timing the bolt travel. This a carbine upper?

[Ruiner]

Are you riding the charging handle forward by chance?

[pm123]

Are you riding the charging handle forward by chance?

I'm not sure what you mean by this. Do you mean pull it back until it locks, and then push the handle in again? Because yes I do this. Should I be leaving the charging handle out? The issue is when I first pull the handle back, lock it, load a mag and then press the button to release the bolt to chamber it. About 8 times today it did not chamber and the action was left open. A couple times it was only a little open and I used the forward assist button. The rest of the time I needed to manually pull the charging handle back again and release to refeed the round. It just seems like when it's locked on the bolt release it doesn't have enough power to load.

Clutchy, I do not know what you mean by the feed ramps. I have a cmmg upper with a 22" bull barrel. I'll add some gun oil on the CBG, I have not cleaned it, and there's maybe only 400 rounds total through it right now. So maybe a break in period is needed?

[markw]

"Riding the slide or handle" is more common in pistols. It's when someone pulls the slide back to chamber the first round and then instead of letting the slide go, they hold onto it as it moves forward. Same with the charging handle. Sounds like you're locking the bolt back. Did you try different ammo? I don't think it's a feedramp issue, sounds like an ammo issue, or the spring doesn't have enough oomph. When you're shooting it, does it function fine other than that first round? Are you forcing an 11th round in the magazine?? Some 10 rounders will take an 11th round, but it's super tight and won't strip off easy.

[pm123]

I'm pretty sure I'm only loading 10 rounds... could be 11, there were 4 different people loading mags. We shot only PCM 62gr stuff today. Last week I tried federal, hornady, and pcm. I guess I'll have to take it out a few more times to narrow it down. The issue was almost entirely when the bolt was locked and trying to chamber the first round. If I manually pulled the handle back and released from that point it loaded. There were maybe 2 or 3 rounds that got punched and didn't fire. I reloaded them and they took a couple times to fire off but did eventually go.

[clutchy]

[IMG][/IMG]

OK: So what Mark is talking about is circled in number 3. You want to pull it back to lock back the bolt and then push it forward and then when you're ready use the bolt release which is on the other side of the rifle.

IF you can; make sure the bolt is closed and then push out the pins in #1 & 2 and take a picture inside of the upper with the bolt removed pointed towards the barrel. Remember don't dryfire with the upper off unless you're holding the hammer.


if you haven't lubed the thing in 400 rounds it could be that... but if you've been single firing it the entire time it's certainly something else.

did you do a function check?

http://www.youtube.com/watch?v=iA_Vkb2UB1w

http://www.youtube.com/watch?NR=1&v=jq4KfUaVp8M&feature=endscreen

2nd vid function test is @ ~1:45.

[SocomM4]

Why not take the whole rifle into SBR and ask them?

They're pretty smart.

[ninjamaster]

If you load too many rounds in a magazine it will sometimes bind up the BCG as it slides forward. I have seen a few standard cap mags with 10 round limiting blocks that barely gave enough room for 10 rounds. This will also cause a FTF or even bind up the BCG on first round.

Fully load a mag, say 10 rounds, insert into the rifle with the bolt closed, then try to cycle the BCG with Charging Handle. If it binds up then this is the reverse of what's happening. I have seen this when loading 31 rounds in a 30 round mag. A friend who contracts in Astan told me he only loads 28 rounds in his 30's(AK47) do to binding issues and malfunctions. Just something to look at.